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The map displays volcanoes, earthquakes, monitoring instruments, and past lava flows.

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Volcano Hazards Program

Find U.S. Volcano

There are about 170 potentially active volcanoes in the U.S. The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from volcanic unrest and eruption through our National Volcano Early Warning System. We deliver forecasts, warnings, and information about volcano hazards based on a scientific understanding of volcanic behavior.

Learn more about NVEWS

Volcano Activity Notifications

Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi

USGS Volcano Observatories release regular updates and notifications to communicate increases or decreases in volcanic activity and explain unusual or hazardous circumstances. 

Get Latest Updates

Volcano Hazards Assessments

Mount Rainier seen from Puyallup, Washington

Long-term hazards assessments identify locations at risk from volcanic hazards. They are released as high-resolution hazards-zonation maps with accompanying explanations, which help guide eruption preparedness plans.

View Assessments

U.S. Volcano Observatories

Volcano Observatory staff monitor, research, and issue formal notices of activity for volcanoes in assigned geographic areas. Scientists also assess volcano hazards and work with communities to prepare for volcanic eruptions.

Learn More

News

Photo & Video Chronology — April 9, 2026 — Kīlauea summit episode 44

Photo & Video Chronology — April 9, 2026 — Kīlauea summit episode 44

Volcano Watch — Caldera clues: tephra deposits from Kīlauea’s past

Volcano Watch — Caldera clues: tephra deposits from Kīlauea’s past

New open access articles on Mauna Loa 2022 eruption

New open access articles on Mauna Loa 2022 eruption

View All

Publications

Yellowstone Volcano Observatory 2024 annual report Yellowstone Volcano Observatory 2024 annual report

The Yellowstone Volcano Observatory (YVO) monitors volcanic and hydrothermal activity associated with the Yellowstone magmatic system, carries out research into magmatic processes occurring beneath Yellowstone Caldera, and issues timely warnings and guidance related to potential future geologic hazards. YVO is a collaborative consortium that includes the U.S. Geological Survey (USGS)...
Authors
Yellowstone Volcano Observatory
By
Volcano Hazards Program, Volcano Science Center

Determining Volcanic Risk in Auckland (DEVORA) Research Programme—A transdisciplinary approach to address the challenge of distributed volcanism in an urban environment Determining Volcanic Risk in Auckland (DEVORA) Research Programme—A transdisciplinary approach to address the challenge of distributed volcanism in an urban environment

The Determining Volcanic Risk in Auckland (DEVORA) Research Programme was launched in 2008 to address the challenges associated with monogenetic volcanism in an urban setting and to enhance volcanic risk management in Tāmaki Makaurau Auckland in Aotearoa New Zealand. It is a multi-agency, increasingly transdisciplinary (defined here as research that transcends traditional disciplinary...
Authors
Jan M. Lindsay, Elaine R. Smid, Natalie Balfour, Natalia I. Deligne, Angela Doherty, Annahlise Hall, Tracy Howe, Gill Jolly, Graham Leonard, Kate Lewis, Craig A. Miller, Ema Nersezova, Ross Roberts, Richard E. Smith, Thomas Stolberger, Kelvin Tapuke, Thomas M. Wilson
By
Volcano Hazards Program, Volcano Science Center

Advances in volcano monitoring driven by the first decade of Sentinel-1 observations Advances in volcano monitoring driven by the first decade of Sentinel-1 observations

Sentinel-1 has transformed how satellite radar data (SAR and InSAR) are used in volcanology. The systematic, long-term archive and open-access policy means that volcano observatories and research organisations have invested in integrating Sentinel-1 datasets into their monitoring systems. We identify 233 high priority volcanoes and estimate that Sentinel-1 data has been used in peer...
Authors
Juliet Biggs, Nantheera Anantrasirichai, Kyle R. Anderson, Valerie Cayol, Edna W. Dualeh, Quentin Dumont, Susanna K. Ebmeier, Jean Luc Froger, Matthew Gaddes, Federico Galleto, Pablo J. Gonzales, Ian Hamling, Andrew Hooper, Milan Lazecky, Camila Novoa Lizama, Matthew E. Pritchard
By
Volcano Hazards Program, Volcano Science Center
View All
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Melt Inclusions

Transmitted light photographs of melt inclusions trapped in quartz phenocrysts from the Sciuvechi lava at Pantelleria, Italy. Reprinted from Lowenstern (1994: American Mineralogist 79:353-369). (A) Inclusion P32-39 (60µm in maximum diameter) was experimentally heated to ~825°C and then cooled to 700°C, at which time three small vapor bubbles nucleated. All bubbles nucleated either on the quartz wall or a refractory quartz bleb (q). None nucleated on a small droplet of hydrosaline melt (h), which is ~60-70wt.% molten NaCl, and was trapped along with the melt during crystallization of the quartz. (B) Two hydrosaline melt droplets (4 µm diameter each) were present within P32-49.1 (105 µm in maximum diamter). During heating at 875°C, some opaque crystals (o) remained unmelted but were dissolved above 900°C. (C) During cooling, below 490± 15°C, the hydrosaline melts crystallized and could not be clearly viewed except at 1250X magnification (D and E, for left and right hydrosaline melts, respectively), which showed them to consist of host glass (m), a vapor (+ liquid?) bubble, and a white crystal with cubic habit (presumably halite). The host crystal was flipped and rotated before photographing D and E.

Volcano Hazards Program | U.S. Geological Survey Skip to main content
U.S. flag

An official website of the United States government

Filters

Learn More

The map displays volcanoes, earthquakes, monitoring instruments, and past lava flows.

Get Help

Earthquake Plots
To view an earthquake cross-sectional plot, click "Draw Plot" to start drawing on the map. Once the plot area is selected, click on "View Plot" to view chart or "Clear Plot" to start over.

Results
Filters

Learn More

The map displays volcanoes, earthquakes, monitoring instruments, and past lava flows.

Get Help

Earthquake Plots
To view an earthquake cross-sectional plot, click "Draw Plot" to start drawing on the map. Once the plot area is selected, click on "View Plot" to view chart or "Clear Plot" to start over.

Settings

x

Map Legend

x

Map Legend

Results

Volcano Hazards Program

Find U.S. Volcano

There are about 170 potentially active volcanoes in the U.S. The mission of the USGS Volcano Hazards Program is to enhance public safety and minimize social and economic disruption from volcanic unrest and eruption through our National Volcano Early Warning System. We deliver forecasts, warnings, and information about volcano hazards based on a scientific understanding of volcanic behavior.

Learn more about NVEWS

Volcano Activity Notifications

Ash-rich plume rises out of Halemaʻumaʻu Crater, Kilauea Volcano Hawaiʻi

USGS Volcano Observatories release regular updates and notifications to communicate increases or decreases in volcanic activity and explain unusual or hazardous circumstances. 

Get Latest Updates

Volcano Hazards Assessments

Mount Rainier seen from Puyallup, Washington

Long-term hazards assessments identify locations at risk from volcanic hazards. They are released as high-resolution hazards-zonation maps with accompanying explanations, which help guide eruption preparedness plans.

View Assessments

U.S. Volcano Observatories

Volcano Observatory staff monitor, research, and issue formal notices of activity for volcanoes in assigned geographic areas. Scientists also assess volcano hazards and work with communities to prepare for volcanic eruptions.

Learn More

News

Photo & Video Chronology — April 9, 2026 — Kīlauea summit episode 44

Photo & Video Chronology — April 9, 2026 — Kīlauea summit episode 44

Volcano Watch — Caldera clues: tephra deposits from Kīlauea’s past

Volcano Watch — Caldera clues: tephra deposits from Kīlauea’s past

New open access articles on Mauna Loa 2022 eruption

New open access articles on Mauna Loa 2022 eruption

View All

Publications

Yellowstone Volcano Observatory 2024 annual report Yellowstone Volcano Observatory 2024 annual report

The Yellowstone Volcano Observatory (YVO) monitors volcanic and hydrothermal activity associated with the Yellowstone magmatic system, carries out research into magmatic processes occurring beneath Yellowstone Caldera, and issues timely warnings and guidance related to potential future geologic hazards. YVO is a collaborative consortium that includes the U.S. Geological Survey (USGS)...
Authors
Yellowstone Volcano Observatory
By
Volcano Hazards Program, Volcano Science Center

Determining Volcanic Risk in Auckland (DEVORA) Research Programme—A transdisciplinary approach to address the challenge of distributed volcanism in an urban environment Determining Volcanic Risk in Auckland (DEVORA) Research Programme—A transdisciplinary approach to address the challenge of distributed volcanism in an urban environment

The Determining Volcanic Risk in Auckland (DEVORA) Research Programme was launched in 2008 to address the challenges associated with monogenetic volcanism in an urban setting and to enhance volcanic risk management in Tāmaki Makaurau Auckland in Aotearoa New Zealand. It is a multi-agency, increasingly transdisciplinary (defined here as research that transcends traditional disciplinary...
Authors
Jan M. Lindsay, Elaine R. Smid, Natalie Balfour, Natalia I. Deligne, Angela Doherty, Annahlise Hall, Tracy Howe, Gill Jolly, Graham Leonard, Kate Lewis, Craig A. Miller, Ema Nersezova, Ross Roberts, Richard E. Smith, Thomas Stolberger, Kelvin Tapuke, Thomas M. Wilson
By
Volcano Hazards Program, Volcano Science Center

Advances in volcano monitoring driven by the first decade of Sentinel-1 observations Advances in volcano monitoring driven by the first decade of Sentinel-1 observations

Sentinel-1 has transformed how satellite radar data (SAR and InSAR) are used in volcanology. The systematic, long-term archive and open-access policy means that volcano observatories and research organisations have invested in integrating Sentinel-1 datasets into their monitoring systems. We identify 233 high priority volcanoes and estimate that Sentinel-1 data has been used in peer...
Authors
Juliet Biggs, Nantheera Anantrasirichai, Kyle R. Anderson, Valerie Cayol, Edna W. Dualeh, Quentin Dumont, Susanna K. Ebmeier, Jean Luc Froger, Matthew Gaddes, Federico Galleto, Pablo J. Gonzales, Ian Hamling, Andrew Hooper, Milan Lazecky, Camila Novoa Lizama, Matthew E. Pritchard
By
Volcano Hazards Program, Volcano Science Center
View All
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